What causes pectus excavatum?
While the cause of this abnormality is unknown, the fact that it tends to occur in families suggests that genetics may play a role. Excessive growth and structural abnormalities of the cartilage (tough, connective tissue) of the ribs and breastbone are present in pectus excavatum. Also, pectus excavatum is seen in some inherited connective tissue disorders such as Marfan syndrome, homocystinuria, and Ehlers-Danlos syndrome.
